Cardiac mapping is used to locate aberrant electrical pathways and currents emanating within the heart. The aberrant pathways cause the contractions of the heart muscle to take on peculiar and life threatening patterns or dysrhythmias.
Intracardiac mapping requires the careful positioning of an array of multiple electrodes within the heart. Various structures for these multiple electrode mapping arrays have been developed or proposed.
For example, Hess U.S. Pat. Nos. 4,573,473 and 4,690,148 and Desai U.S. Pat. No. 4,940,064 show the use of generally planar mapping arrays. Chilson U.S. Pat. No. 4,699,147 shows the use of a three dimensional basket mapping array. Gelinas U.S. Pat. No. 4,522,212 shows a spring apart array of electrode supporting fingers.
Regardless of the type of mapping array used, the physician is called upon to remotely move and manipulate the array within the heart in various ways. First, the physician must maneuver the array through a main vein or artery into a selected heart chamber. Then, the physician must locate the array at the desired endocardial location. Then, the physician must further move the array at the desire location to assure that all aberrant electrical pathways, if present, are located.
The development of prior mapping arrays has focused upon the requirements of mapping function itself. The prior development has overlooked the important need to continuously wash the area around the electrodes during the procedure.
The flushing action clears blood and other body fluids away from the electrode, so that reliable mapping signals can be obtained and/or the desired ablation energy can be applied, without attentuation and disruption.